1. Field of the Invention
The present invention relates to an electric connector for an endoscope that connects the endoscope to an external instrument to be combined with the endoscope for use, an endoscope, and a method for assembling the electric connector.
2. Description of the Related Art
An electric connector to which a plurality of cable wires are connected is generally used to electrically connect various electronic instruments together. An electronic endoscope apparatus, an electronic instrument in medical fields, has an electronic endoscope containing a solid image pickup device (hereinafter simply referred to as a CCD) that is inserted into the body cavity to pick up images of the body cavity, and a video processor as an external instrument that executes predetermined signal processing on image pickup signals obtained by the electronic endoscope to generate endoscope video signals. The electronic endoscope and the video processor are connected together by an electric connector to which a plurality of cable wires for the transmission and reception of various signals and the supply of driving power are connected.
For example, Japanese Patent No. 2902654 proposes an electric connector used for electronic endoscope apparatuses. The electric connector proposed in Japanese Patent No. 2902654 will be described with reference to FIGS. 10 and 11.
First, the concept of the configuration of an electronic endoscope apparatus will be described with reference to FIG. 10. An electronic endoscope apparatus 101 is composed of an electronic endoscope 102, a light source device 103, a video processor 106, and a monitor 107.
The electronic endoscope 102 comprises an elongate, flexible insertion portion 108 for insertion into the body cavity, an operation portion 109 provided on a proximal end of the insertion portion 108 and which is grasped and operated by an operator, and a universal cord 110 as a connection cable which extends from the operation portion 109. The insertion portion 108, the operation portion 109, and the universal cord 110 each contain a light guide 111 and a cable wire 112. One end of the light guide 111 is located at a distal end portion of the insertion portion 108. The other end of the light guide 111 is connected to the light source device 103 by a scope connector 113 provided at a proximal end portion of the universal cord 110. One end of the cable wire 112 is connected to a CCD 115 located at a focal position of an objective lens 114 provided at a distal end of the insertion portion 108 and to a part having a predetermined function, such as a switch described below. The other end of the cable wire 112 is connected to an electric connector 120 provided in the scope connector 113.
Although not shown, the operation portion 109 has a bending operation knob that bendably operates a bending portion provided at the distal end portion of the insertion portion 108, a treatment instrument insertion opening through which a treatment instrument is inserted into a treatment instrument channel in the insertion portion 108, and image processing system switches such as a release switch, a freeze switch, and enhance switch which are used to drivingly control the CCD 115 to manipulate motion pictures, still images, and the like.
Further, the operation portion 109 has an air and water feeding button used to feed air or water to the surface of the objective lens 114, located at the distal end portion of the insertion portion 108, a suction button used to suck feculence or water out of the body cavity, and a water forward feeding button used to feed forward cleaning water used to clean the interior of the body cavity. The image processing system switches, provided in the operation portion 109, are connected to the video processor 106 via the electric connector 120, provided in the scope connector 113 of the universal cord 110.
The air and water feeding pump, which feeds air and water, is provided in the light source device 103. A suction pump for suction and a water forward feeding pump for water forward feeding are separately provided from the light source device 103. These pumps perform air and water feeding, suction, and water forward feeding.
The light source device 103 has a light source lamp 116, a condensing lens 117 that condenses illumination light from the light source lamp 116 to allow the light to enter an input end of the light guide 111, located in the scope connector 113, a lighting and dimming control circuit (not shown) for the light source lamp 116, and the above pumps.
The video processor 106 is a signal processing device (the video processor 106 is hereinafter also referred to as the signal processing device) having a drive circuit 104 that drivingly controls the CCD 115, provided at the distal end of the insertion portion 108 of the electronic endoscope 102, and a signal processing circuit 105 that processes image pickup signals photoelectrically converted by the CCD 115 to generate endoscope video signals. The light source device 103 and the video processor 106 are integrally formed.
The monitor 107 displays endoscope images corresponding to video signals processed by the signal processing circuit 105 in the video processor 106.
The scope connector 113, provided at the proximal end of the universal cord 110, has the electric connector 120 which connects an incident end of the light guide 111 to the light source device 103 and to which the other end of the cable wire 112 in the electronic endoscope 102 is connected, as described above.
The electric connector 120 couples to a connection plug 122 connected to one end of a connection cord 121 comprising a plurality of cables for connection to the video processor 106, serving as an external instrument used in combination with the electronic endoscope 102.
A connection plug 123 similar to the connection plug 122 is provided at the other end of the connection cord 121. The connection plug 123 is coupled to an electric connector 124 provided in the video processor 106. The electric connector 124, provided in the video processor 106, has a configuration substantially similar to that of the electric connector 120, described above.
That is, the electric connector 120 connects to the cable wire 112 comprising a signal wire that connects the CCD 115, provided at the distal end portion of the insertion portion 108, to the video processor 106 in order to transmit and receive a CCD driving control signal, an image pickup signal, a driving power supply, and the like, a signal wire that connects the image processing system switches, provided on the operation portion 109, to the video processor 106, and a signal wire that connects the light source device 103 to the video processor 106 to allow the video processor 106 to perform dimming control on the light source device 103. The electric connector 120 also couples to a connection plug 122 of the connection cord 121 for connection to the video processor 106.
The electric connector 120, provided in the scope connector 113, will be described with reference to FIG. 11. The electric connector 124, provided in the video processor 106, has a configuration substantially similar to that of the electric connector 120 of the scope connector 113 except for the pin configuration, water-tight structure, and the like. Accordingly, the description of the electric connector 124 is omitted.
The electric connector 120 has a cylindrical base 131 including a flange 132 provided around the outer periphery of the base 131 for threadable attachment to the scope connector 113. A cylindrical insulating frame 135 is fitted into the inner periphery of the base 131. A cylindrical guide member 136 is further fitted into the cylindrical insulating frame 135. An engaging projection provided on the inner periphery of a proximal end of a guide member 136 has a cover member 138, and an insulator 139 and a circuit board 141 fixed via a circuit board fastener 142 to a rear surface of the cover member 138 so that the insulator 139 lies on top of the circuit board 141. The guide member 136 is fixedly positioned by a positioning pin 143 engagingly fitted into the base 131 and the cylindrical insulating frame 135. A water-tight packing is interposed between the outer periphery of the circuit board fastener 142 and the inner periphery of the proximal end of the base 131. A cylindrical shield frame 145 is threadably attached to the proximal end of the circuit board fastener 142. A shield member 146 is fixedly attached to the proximal end of the shield frame 145 and has an opening in which the cable wire 112 is inserted. The cable wire 112 is placed in the opening in the shield member 146. The cable wire 112, caught in a cushion member 147, is fixed to a shield member 146 via a cable fastening plate 148 and a screw 149.
Solid wire pins 152 that are a plurality of solid wire terminals, coaxial pins 154 that are a plurality of coaxial terminals, and a post pin 153 penetrate the cover member 138, insulator 139, and circuit board 141, provided inside the proximal end of the guide member 136. Solid wires 155 constituting the cable wire 112 are connected to the solid wire pins 152. A core wire and a shield wire of a coaxial wire 156 constituting the cable wire 112 are connected to the coaxial pins 154. The core wire of the coaxial wire 156 may be connected to one of the solid wire pins 152, while the shield wire may be connected to another solid wire pin 152. The post pin 153 releases static electricity generated when an operator's hand or the like touches any pin.
Moreover, each of the cover member 138, the insulator 139, and the circuit board 141 has a vent 161 that penetrates each of the cover member 138, the insulator 139, and the circuit board 141. A permeable waterproof sheet through which air is passed but not any liquid is attached to the vent 161.
The solid wires 155, connected to the solid wire pins 152, each have a core wire around which an insulating coating is provided. Each of the coaxial wires 156, connected to the coaxial pins 154, comprises a core wire around which an insulating coating is provided and a shield wire which is located around the outer periphery of the insulating coating of the core wire and around which an insulating coating is further provided. Each of the solid wire pins 152 are basically formed only of a pin to which the core wire of the solid wire 155 is connected. Further, each of the coaxial pins 154 comprises a core wire portion and a shield portion which are insulated and isolated from each other and to which the core wire and shield wire, respectively, of the coaxial wire 156 are connected.
The connection plug 122 of the connection cord 121, installed on the electric connector 120 configured as described above, has a pin receiver into which the solid wire pin 152 and the coaxial pin 154 are inserted.
The connection plug 122 of the connection cord 121 connected to the video processor 106 is coupled to the electric connector 120 provided in the scope connector 113 to electrically connect the electronic endoscope 102 to the video processor 106. This allows the supply of driving power to the CCD 115 and the transmission and reception of image pickup signals, various image processing system control signals, and the like. Moreover, the light source device 103 and the video processor 106 are electrically connected together to allow the video processor 106 to perform dimming control and the like.
To remove or replace, for repair, any part of the electronic endoscope 102 using the electric connector 120 configured as described, the following operation is performed. The cable wire 112 is disconnected from the solid wire pins 152 and the coaxial pins 154. Action such as part replacement which is required for the repair is taken. An end of the cable wire 112 is connected back to the solid wire pins 152 and the coaxial pins 154.
For example, to remove, from the electronic endoscope 102 including the CCD 115, an image pickup unit of the electronic endoscope 102 which provides functions for image pickup, the image pickup unit and the cable wire 112 connected to the image pickup unit are removed from the electronic endoscope 102.
Further, to remove any of the electric switches such as the image processing system switches, provided on the operation portion 109, from the electronic endoscope 102 for replacement owing to a defect in the electric switch, that electric switch and the cable wire 112 connected to the electric switch are removed from the electronic endoscope 102.